I dislike calling it the "American Years of Lead" because the Italian YoL involved tons of communist and anarchist violence to at least *try* and match the state's. But since 2000 we can count such violence on our hands in the USA:
Maurice Clemmons, WA 2009
Chris Monfort, WA 2009
Micah X, TX 2016
add a skeleton here at some point
about 16 hours ago